Means for guiding plansifter brushes



Feb. 19, 1935. A. TElcHMANN MEANS FOR GUIDING PLANSIFTER BRUSHES Filed Aug. 12, 1932 A 2 sheets-sheet 1 Figi Feb- 19, 1935. A. TEICHMANN 1,991,585

MEANS FOR GUIDING PLANSIFTER BRUSHES Filed Aug. l2, 1952 2 Sheets-Sheet 2 www Rmx-3 Patented Feb. 19, 1935l MEANS FOR GUIDING PLANSIFTER BRUSHES Albert Teichmann, Zeitz, Germany Application August 12, 1932, serial No. 628,450 In Germany August 21, 1931 f.

1 Claim.

For the purpose of keeping the sieves clean in plansifters, brushes are employed which have lateral rolling pivots or rider brushes, which are guided by a rail closed in itself. Brushes with 5 lateral roller pivots have the disadvantage of unequal to-and-fro movement of the brush body, particularly in the case of brushes with a large radius of oscillation. The outer portion of the covering on both sides of the brush is subjected l to greater wear than the inner portion, and the outer parts of the sieve surfaces are accordingly attacked more than the central parts. In the case of rider brushes, which are guided by a closed rail, the brush does not run smoothly, and

l the turning in the curves is effected very slowly,

quite irrespectively of whether the guiding means of the brush consist of stationary slide jaws, rollers, or thrust bundles. On the other hand, in brushes with a lateral rolling pivot, the continuously rolling rollers `of the pivots cause undesirable noises, andV in consequence of their continuous running they are subjected to rapid wear. In addition to this, when such brushes are employed with lateral rollingV pivots, special guiding strips have to be provided, which are inconvenient and expensive, and this also applies to operating plansifters by means of rider brushes, where the guiding rail extends over the entire track of the brush, that is to Vsay, form a rail closed in itself. v

All these disadvantages are obviated by the present invention, which consists in a device for guiding plansifter brushes, and is essentially characterized by the fact that upon each rectilinear path of the brush track is provided, a rail engaging in a recess in the brush, known in connection with rider brushes, and a semicircular arcuate piece at each of the turning positions, for a pivot, known from roller pivots-fitted on 40 the inside of the brush. In this way is obtained a simplified guide for the brush, since only upon each rectilinear path is a straight rail required, and the combination of rider brush and pivot 45 brush produces the result that upon rectilinear paths of the brush the momentum thereof is uniform on both sides of the straight rail, whereas at the turning points it only comes into action on oneside, that is to say, wholly and entirely 50 in lthe direction of the turning movement. This yields a quick, reliable and smooth running in a rectilinear direction, and an easy, reliable and quick turning in the curves.v Furthermore the wear ofthe brush covering on both sides of the 55. brush, and the parts of the sieve surfaces that vof the discharge passage o. y, which comes into operation at the turning come into contact with the/covering, are equalized. One form 'of the construction of the invention is illustrated in the accompanying drawings, in which v Fig. 1 shows the under side of a brush according to the invention. j

Fig. 2 is a side view of -the brush, and

Fig. 3ra top plan thereof. 1

Fig. 4 shows a section on the line A-A in Fig. 3.

Fig. 5 is a cross section through the sieve frame and Fig. 6 shows the sieve frame in plan. l

The brush, consisting of the brush holder a, the upper brush covering b, and the lower brush covering c, is, according to the invention, so constructed, that it unites in itself a roller pivoted brush and a rider brush. For this purpose it is provided on the under side, like a rider brush, with a recess' formed by two strips or ledges e, which serve for its guidance upon each Yrectilinear portion d, of its track. On the inner side, however, `it has, like a roller pivot brush, a pivot g, which engages at the turning positions,V in a'stationary guiding piece f, of semicircular shape, secured to the boundary strip or bar n, This swing pivot positions, helps the brush to turn more quickly, and it is free from disadvantages of vthe guiding rollers used in ordinary roller pivot brushes, which are in constant rolling movement. The rails d, which guide the brushes on the straight parts of their path, only extend to the turning positions. At the ends they may be connected with semicircularly curved flat iron bars h, which bear upon the collecting floor, and the ends of which intersect the bars p forming the boundary of the discharge passage o.

The apparatus described operates in the following manner:-

In the longitudinal direction the brushes run along on the guiding rail d like any rider brush. 'Ihe guide of the brush is therefore located, during the straight longitudinal run, in the middle of the brush, and cooperates with the strip e on the under side of the brush. When the brush is turning, however, it leaves the rail guide d, and is then held laterally by its pivot g and the guiding piece f arranged above the discharge passage, in such a way that it can execute the turn quickly with frictionless guiding, and at the end thereof, when passing into the rectilinear direction again, it receives guidance from the other rail d.

What I claim is:-

In a screen having a central longitudinally extending discharge opening, guide rails on opposite sides of the opening terminating short of the ends of the screen, guide members bridging the opening on a line withl the ends of the rails, said members having U-shaped sockets therein, a brush movable `over the screen,l said 'fr brush having a. recess therein for slidably engaging one of the rails. a. pivotmember carried by the inner end of the brush and adapted to Y AUBERT 

